It is midnight in Costa Rica. On the fringe of the jungle, the beautiful red-and-orange flowers of the Hamelia plant are about to open. As soon as this happens, groups of tiny creatures, called hummingbird flower mites,1 which have been waiting for dinner-time to arrive, rush inside the flowers and begin gorging on the pollen.2 Next morning, breakfast includes the flowers’ nectar, which is produced just before dawn. With their voracious appetites, the hummingbird flower mites may eat up to 40% of the nectar and 50% of the pollen.3 Meal over, they settle down to the serious business of courtship, mating, and (for the females) egg-laying.4

A few hours after dawn a serious problem arises. The Hamelia blossoms start to wilt and then fall off by noon, so that new accommodation is urgently needed.5 Some mites march out of their flowers and take up positions on the same flower cluster next to new flower buds to await their opening and the next midnight feast. Others use an even more sophisticated approach to get themselves to a brand new neighbourhood.

During the day, hummingbirds are attracted by the brilliant colours of the Hamelia flowers. With a wingbeat of 50–80 times per second,6 a hummingbird hovers for 1–5 seconds as it thrusts its bill deep into a flower and drinks the nectar. This calls for urgent action by the mites that live there—first, to avoid the bird’s flicking tongue and so becoming a protein supplement to its diet of nectar. Second, to hitch a ride on a hummingbird aerial taxi that may take them to a new home, a fresh food supply, and new mates.

In the five seconds before the hummingbird flies off to another flower, some of the mites scramble aboard its bill and dash for the shelter of a nostril. The mites are only 0.5 mm (two-hundredths of an inch) long, and can move at the rate of 12 body-lengths per second), so they can travel about 3 cm in five seconds. Interestingly, a cheetah, moving at its maximum speed of about 100 km/h, is also doing about 12 body-lengths per second….

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